The Conference Board‘s confidence index rose for a second straight month, jumping to 76.2 in May. The index is now at its highest since February 2008. The two-month cumulative gain of 14.3 points is the largest since late 2011.

The general thinking is that the Board’s confidence index is driven mostly by changes in the labor market. But the recent jump may reflect wealth more than work.

The survey shows consumers view labor markets a bit more positively in May than they did in April, but the shares of those who think jobs are “hard to get” or are “plentiful” have not shifted much in the past six months.

The holding pattern mirrors reality. Unless the upcoming May payrolls report — scheduled for June 7 — shows a significant change in the numbers, hiring is running at a 196,000 monthly rate so far in 2013, up only a bit from the 183,000 pace in 2012.

What has changed sharply for households is the wealth — at least on paper — accumulating from home values and stock prices.

Home prices nationally were up 10.2% in the year ended in the first quarter, according to Tuesday’s S&P/Case-Shiller report. To be sure, the report says home prices are only back to where they were in 2003. But the days of double-digit declines are over. Plus, many homeowners who once owed more than their homes were worth are finally ekeing out gains in their home equity.

The stock market’s surge is also contributing to consumer optimism. It’s probably no surprise that the biggest two-month jump in confidence was among higher-income households who are more likely to own stock.

Consumers have done a complete switcheroo on how they view stocks. Last June, only 24.5% of consumers expected stock prices to increase in the next year and 42% anticipated a drop. Fast forward to now: 40.0% think equity prices will increase over the next 12 months, while only 26.2% expect a decline.

Consumers who feel wealthier tend to feel more comfortable about spending [or at least feel they can save less out of current incomes.]

But there is reason to remain cautious about the consumer outlook. Stock prices can fall quickly and sharply. Sustained consumer optimism will depend on stronger job growth.

Plus, the link between shopping and net worth — the so-called wealth effect — has probably diminished. Older workers saving for retirement are trying to make up for the years lost during the financial crisis, and banks remain reluctant to make home-equity loans. That means a happier, wealthier consumer sector may not translate to the type of demand growth the U.S. enjoyed in previous years.

About Real Time Economics

Real Time Economics offers exclusive news, analysis and commentary on the U.S. and global economy, central bank policy and economics. Send news items, comments and questions to the editors and reporters below or email realtimeeconomics@wsj.com.